Image-Reading Device

ABSTRACT

An image-reading device is provided that includes a reading component configured to read a document, a document holding portion, a detector detecting a position of the document holding portion, a power supply device that supplies power to the reading component, and a power supply control device that controls power supplied by the power supply device to the reading component. The power supply control device determines whether a change in the position of the document holding portion has occurred based on the position of the document holding portion detected by the detector. When a change in position is detected and the image reading device is not performing document reading, the power supplied to the reading component is reduced. If a change in position is detected while the image reading device is performing document reading, the power supplied to the reading component is maintained.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation application of prior U.S. applicationSer. No. 13/626,562, filed Sep. 25, 2012, which claims priority fromJapanese Patent Application No. 2011-286379, filed on Dec. 27, 2011 andJapanese Patent Application No. 2012-096788, filed on Apr. 20, 2012,which are incorporated herein by reference.

FIELD

The disclosure relates to an image-reading device that reads a document,and more specifically, to an image-reading device that controls powersupply to reduce power consumed by reading components used for documentreading.

BACKGROUND

In order to achieve power savings, a known image-reading device, forexample, a scanner, is configured to enter a power saving mode to reducepower consumed by reading components used for document reading while thescanner is not in an operating condition.

A known scanner, as an example of an image-reading device that controlspower, includes a retractable document mount that is capable of openingand closing with respect to a main body of the known scanner. The knownscanner is configured to turn itself on or off in accordance with theopening or closing of the document mount.

SUMMARY

The known scanner is configured to turn itself on or off in accordancewith opening or closing of the document mount. When the document mountis changed to an unused position during document reading, the knownscanner turns itself off during the document reading and this maydetrimentally influence image reading quality. The configuration inwhich turning on or off of power of the known scanner is controlled bythe opening or closing of the document mount provides usability. Thus,the scanner not having such a configuration may reduce user convenience.

According to aspects of the disclosure, an image-reading deviceconfigured to control power supply and achieve image-reading quality anduser convenience may be accomplished.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure and thefeatures and advantages thereof, reference now is made to the followingdescriptions taken in connection with the accompanying drawing.

FIG. 1 depicts a scanner in an illustrative embodiment according to oneor more aspects of the disclosure, wherein a document feed tray isclosed.

FIG. 2 depicts the scanner in the illustrative embodiment according toone or more aspects of the disclosure, wherein the document feed tray isopened.

FIG. 3 depicts an internal configuration of the scanner of FIG. 1 in theillustrative embodiment according to one or more aspects of thedisclosure.

FIG. 4 depicts the internal configuration of the scanner of FIG. 2 inthe illustrative embodiment according to one or more aspects of thedisclosure.

FIG. 5 is a block diagram depicting an electric configuration of thescanner in the illustrative embodiment according to one or more aspectsof the disclosure.

FIG. 6 is a perspective view depicting a power supply control system inthe illustrative embodiment according to one or more aspects of thedisclosure.

FIG. 7 depicts a relationship between each mode and a condition of powersupply to each component in the illustrative embodiment according to oneor more aspects of the disclosure.

FIG. 8 is a flowchart depicting a mode switching process in theillustrative embodiment according to one or more aspects of thedisclosure.

FIG. 9 is a flowchart depicting a second power-saving mode executingprocess in the illustrative embodiment according to one or more aspectsof the disclosure.

FIG. 10 is a flowchart depicting a power saving mode switching processin the illustrative embodiment according to one or more aspects of thedisclosure.

DETAILED DESCRIPTION

Hereinafter, an illustrative embodiment in which an image-reading deviceaccording to the aspects of the disclosure may be implemented isdescribed in detail with reference to the accompanying drawings. In theillustrative embodiment, the aspects of the disclosure may be applied toa scanner that may have a power saving mode for reducing powerconsumption in the scanner.

As depicted in FIGS. 1 and 2, a scanner 100 may comprise a housing 6, adocument holding portion such as a document feed tray 91, and a documentdischarge tray 92. Housing 6 may cover a main body of scanner 100.Document feed tray 91 may be configured to cover or uncover an uppersurface 6A of housing 6 and be opened or closed with respect to scanner100. Document discharge tray 92 may be disposed at a lower part ofscanner 100. In FIG. 1, the side on which document discharge tray 92 maybe disposed may be defined as the front of scanner 100. The right, left,front, and rear of scanner 100 may be defined when scanner 100 isdisposed in an orientation in which it is intended to be used, and thedefined directions may be applicable to the drawings of FIGS. 2-4.

Document feed tray 91 may be supported by housing 6 so as to bepivotable about a rotation axis X that may be located at a rearwardlyupward position with respect to housing 6 to extend along a right-leftdirection. When document feed tray 91 is pivoted about rotation axis Xto be opened from a position where document feed tray 91 may cover uppersurface 6A as depicted in FIG. 1, document feed tray 91 may be changedto a position where document feed tray 91 may allow a document holdingsurface 91A to face upward at a rearward part of housing 6 as depictedin FIG. 2. In the illustrative embodiment, the position where documentholding surface 91A may be exposed as depicted in FIG. 2 may be referredto as a “used position” of document feed tray 91 and the position wheredocument holding surface 91A may not be exposed as depicted in FIG. 1may be referred to as an “unused position” of document feed tray 91. Inthe used position, document feed tray 91 may be configured to hold oneor more documents that have not been read yet. In the unused position,document feed tray 91 may be configured not to hold any documentsbecause document feed tray 91 may not allow document holding surface 91Ato appear in the unused position.

Document discharge tray 92 may be disposed at the lower part of housing6 and may be configured to be inserted into or be drawn from housing 6along a front-rear direction. As depicted in FIG. 2, document dischargetray 92 may be configured to be drawn forward with respect to housing 6.In the illustrative embodiment, the position where document dischargetray 92 may be drawn forward with respect to housing 6 as depicted inFIG. 2 may be referred to as a “used position” of document dischargetray 92 and the position where document discharge tray 92 may beaccommodated in housing 6 as depicted in FIG. 1 may be referred to as an“unused position” of document discharge tray 92. Similar to documentfeed tray 91, in the used position, document discharge tray 92 may beconfigured to hold one or more documents that have been read. In theunused position, document discharge tray 92 may be configured not tohold any documents.

As depicted in FIG. 2, housing 6 may comprise an operating panel 40 thatmay comprise a keypad 41 and a display unit 42 at upper surface 6A.Keypad 41 may comprise various buttons (e.g., a start key, a stop key,and numeric keys). Display unit 42 may comprise a liquid crystaldisplay. When document feed tray 91 is located in the unused position,input operations on operating panel 40 by a user may be limited becausedocument feed tray 91 covers operating panel 40 (see FIG. 1). Whendocument feed tray 91 is located in the used position, operating panel40 may appear to allow all input operations by the user.

FIGS. 3 and 4 depict an internal configuration of scanner 100. FIG. 3depicts scanner 100 in which both the document feed tray 91 and documentdischarge tray 92 are located in their unused positions. FIG. 4 depictsscanner 100 in which document feed tray 91 and document discharge tray 9are located in their used positions.

Scanner 100 may comprise a feed roller 62, a first conveyor roller 63,image sensors 21, 22, and a second conveyor roller 64 in its inside. Inthis illustrative embodiment, the reading components, for example, feedroller 62, first conveyor roller 63, image sensors 21, 22, and secondconveyor roller 64, used for document reading may be collectively calledan image reading unit 20. Image reading unit 20 may be configured toread a color image or read a monochrome image only.

One of image sensors 21, 22 may be configured to read an image on oneside of a document and the other of image sensors 21, 22 may beconfigured to read an image on the other side of the document. In eachof image sensors 21, 22, optical elements may be arranged in line alongthe right-left direction (a direction perpendicular to the drawingsurface of FIG. 4). Each of image sensors 21, 22 may be configured toconvert light reflected from the document into electronic signals andoutput the electronic signals. For example, a contact image sensor(“CIS”) or a charge-coupled device (“CCD”) may be employed as imagesensors 21, 22.

Scanner 100 may convey one or more documents 9 held on document feedtray 91 along a direction indicated by an arrow D depicted in FIGS. 2and 4 from document feed tray 91 to document discharge tray 92. Morespecifically, in scanner 100, document feed tray 91 may be located inthe used position for setting one or more documents 9 on document feedtray 91. As depicted in FIG. 4, the user may set one or more documents 9on document feed tray 91. The one or more documents 9 held on documentfeed tray 91 may move toward feed roller 62 by their own weight. Then,feed roller 62 may convey documents 9, one by one, downstream along aconveying path 61. Image reading unit 20 may read one or both sides ofdocument 9 that is moving in conveying path 61 when document 9 passesimage reading unit 20. After that, scanner 100 may discharge document 9onto document discharge tray 92. That is, document feed tray 91 anddocument discharge tray 92 may constitute a part of conveying path 61.

As depicted in FIG. 3, in scanner 100, when document feed tray 91 islocated in the unused position, conveying path 61 may be curved in asubstantially U-shape manner at rotation axis X of document feed tray91. Therefore, when document feed tray 91 is located in the unusedposition, scanner 100 may be configured to not perform document readingby image reading unit 20.

Scanner 100 may further comprise a control device 10 and a power supplycontrol system 50 in its inside as well as image reading unit 20.Control device 10 may be configured to control image reading unit 20.Power supply control system 50 may be configured to control powersupplied to each unit or component of scanner 100. Control device 10 andpower supply control system 50 will be described in detail later.

An electric configuration of scanner 100 is now described. As depictedin FIG. 5, scanner 100 may comprise image reading unit 20, a detectorsuch as sensor 30, operating panel 40, power supply control system 50,control device 10, a Universal Serial Bus (“USB”) interface (“I/F”) 15and a network interface (“I/F”) 16. Sensor 30 may be configured todetect the position of document feed tray 91 in the used position or inthe unused position. Power supply control system 50 may be configured tocontrol power supplied to each unit or component of scanner 100. Controldevice 10 may be configured to control operations of image reading unit20. USB interface 15 and network interface 16 may be communicationinterfaces for establishing connections between scanner 100 and anoutput destination device, for example an external device.

Control device 10 may comprise a central processing unit (“CPU”) 11, aread-only memory (“ROM”) 12, a random-access memory (“RAM”) 13, and anonvolatile RAM (“NVRAM”) 14. ROM 12 may store firmware that may controlprograms for controlling scanner 100 and various settings as well ascertain setting values. RAM 13 may be used as a workspace fortemporarily storing the control programs read from ROM 12 or as astorage area for temporarily storing image data.

A reading control device, for example CPU 11, may control functions ofeach unit or each component of scanner 100. CPU 11 may store processingresults in RAM 13 or NVRAM 14, in accordance with the control programsread from ROM 13 and signals sent from sensors.

USB interface 15 may be configured to allow scanner 100 to communicatewith the external device. For example, when an USB memory is connectedto USB interface 15, scanner 100 may output read image data to the USBmemory. USB interface 15 may not always be connected with the USB memorybut also can be connected with, for example, a personal computer (“PC”).When USB interface 15 is connected with a PC, scanner 100 may beconfigured to receive various instructions, for example, a scanninginstruction or a setting instruction, from the PC via USB interface 15.

Similar to USB interface 15, network interface 16 may be configured toallow scanner 100 to communicate with the external device. Scanner 100may be configured to output read image data to an external deviceconnected thereto via network interface 16. Scanner 100 may receiveinstructions from the external device via network interface 16.

The connection between scanner 100 and the external device may beestablished via other devices as well as USB interface 15 and networkinterface 16. For example, when scanner 100 comprises a wirelesscommunication interface, scanner 100 may be connected with the externaldevice via wireless communication.

Image reading unit 20 may be configured to read an image on a documentand output the read image as image data, for example, in PDF format.Image reading unit 20 may be further configured to perform a correctionprocess on the image data as required. Image reading unit 20 may outputthe image data to, for example, the external device that may beconnected with scanner 100 via USB interface 15 or network interface 16.

Sensor 30 may be configured to output a signal identifying whetherdocument feed tray 91 is in the used position (an opened state) or inthe unused position (a closed state). Sensor 30 may comprise, forexample, a light-emitting element and a light-receiving element. Whendocument feed tray 91 is located in the used position, sensor 30 may beconfigured such that the light-receiving element may receive light fromthe light-emitting element. When document feed tray 91 is located in theunused position, sensor 30 may be configured such that thelight-receiving element may not receive light from the light-emittingelement due to an interruption.

The power supply control performed in scanner 100 is described below. Asdepicted in FIG. 6, scanner 100 may comprise a power source device 51(an example of a supply device), a switch circuit 52, and a power supplycontrol device 53, collectively forming a power supply control system50. Switch circuit 52 may be configured to distribute the power suppliedfrom power source device 51 to each unit or each component of scanner100. Power supply control device 53 may be configured to control makingand breaking of each switch of switch circuit 52.

Power source device 51 may comprise a circuit that may be configured tobe connected with, for example, a main electricity grid or a battery,and convert the power to an appropriate level to supply to each unit oreach component of scanner 100. Switch circuit 52 may be configured toswitch a power supply condition between supplying or not supplying powerto each unit or each component of scanner 100 in accordance with asignal outputted from power supply control device 53. More specifically,scanner 100 may comprise a power source system for image reading unit20, a power source system for control device 10, and a power sourcesystem for an external interface (for example, USB interface 15 andnetwork interface 16 in this embodiment). Switch circuit 52 may beconfigured to switch the power supply condition between supplying or notsupplying power to each power source system. Power source device 51 maysupply power to sensor 30 and operating panel 40 all the time bybypassing switch circuit 52.

A plurality of power-supply modes are now described below. The pluralityof power-supply modes may be realized by the switching of the powersupply condition by switch circuit 52 between supplying or not supplyingpower to each power source system. The power-supply modes may include apower saving mode for reducing power consumed by one or more of imagereading unit 20 and the other units and components, and a non-powersaving mode for not reducing power consumed by image reading unit 20 andthe other units and components.

More specifically, the non-power saving mode may include a ready mode.In the ready mode, scanner 100 may be allowed to perform image readingfrom a document and data transmission or reception and to receive useroperations through operating panel 40. The power saving mode may includea first power-saving mode and a second power-saving mode. In the firstpower-saving mode, scanner 100 may be allowed to perform datatransmission or reception via USB interface 15, network interface 16, orother interfaces and to receive user operations through operating panel40 but may not be allowed to perform image reading from a document. Inthe second power-saving mode, scanner 100 may not be allowed to performimage reading from a document and data transmission or reception whileoperating panel 40, sensor 30, and power supply control system 50 may beallowed to operate.

FIG. 7 depicts a relationship between each mode and a condition of powersupply to each unit or each component. In FIG. 7, “SUPPLIED” mayrepresent that power is supplied to the unit or the component and “NOTSUPPLIED” may represent that power is not supplied to the unit or thecomponent. As depicted in FIG. 7, in the ready mode, power is suppliedto all of image reading unit 20, control device 10, operating panel 40,the external interface, and sensor 30, and scanner 100 may be allowed toperform a scanning operation. Immediately after scanner 100 is up,scanner 100 may operate in the ready mode. When a condition for shiftingto the first power-saving mode is met during the ready mode, the modemay be changed to the first power-saving mode. When a condition forshifting to the second power-saving mode is met during the ready mode orduring the first power-saving mode, the mode may be changed to thesecond power-saving mode.

In the first power-saving mode, switch circuit 52 may interrupt thepower supply to image reading unit 20. That is, switch circuit 52 mayinterrupt the power supply to image sensors 21, 22, which may consume alarger amount of power, to reduce the power consumption in scanner 100.However, switch circuit 52 may not interrupt the power supply to controldevice 10, operating panel 40, and the external interface to receiveuser operations. When a condition for shifting to the ready mode is met,the mode may be changed to the ready mode.

In the second power-saving mode, switch circuit 20 may interrupt thepower supply to control device 10 and the external interface in additionto image reading unit 20. That is, scanner 100 may not be allowed toperform data transmission or reception to or from the external device.This power supply control may further reduce the power consumption inscanner 100 as compared with the power consumption in scanner 100 in thefirst power-saving mode. However, switch circuit 20 may not interruptthe power supply to sensor 30. That is, sensor 30 may be controlled by acircuit different from control device 10, and thus, sensor 30 may beconfigured to detect the position of document feed tray 91 in the usedposition or in the unused position when scanner 100 is in the secondpower-saving mode. When document feed tray 91 is changed to the usedposition during the second power-saving mode, scanner 100 may determinethat the document feed tray 91 has been changed from the unused positionto the used position based on the detection result of sensor 30 and mayshift to the ready mode. In the second power-saving mode, operatingpanel 40 may be supplied with power. That is, operating panel 40 may becontrolled by a circuit different from control device 10 and may beconfigured to receive user operations when scanner 100 is in the secondpower-saving mode.

More specifically, power supply control device 53 may store a thresholdtime period (e.g., a waiting period) that may be a time at which themode may be changed to the power saving mode. When the elapsed timemeasured by a timer exceeds the threshold time period since a timeperiod during which the document reading may be performed has elapsed ora user operation (for example, an input through operating panel 40 or aninstruction inputted from the external device) has been completed, themode may be changed to the power saving mode. When document feed tray 91is located in the used position at the time the elapsed time beingmeasured exceeds the threshold time period, the mode may be changed tothe first power-saving mode. When document feed tray 91 is located inthe unused position at the time the elapsed time being measured exceedsthe threshold time period, the mode may be changed to the secondpower-saving mode. After the mode is changed to the second power-savingmode, the timer may stop because the power supplied to control device 10that can control the timer is interrupted.

Power supply control device 53 may be configured to output, to switchcircuit 52, a signal for supplying or not supplying power to each powersource system, in accordance with the current mode. Power supply controldevice 53 may be directly supplied with power from power source device51 and configured to work while scanner 100 is in the secondpower-saving mode. Therefore, power supply control device 53 may controlswitch circuit 52 by monitoring an output signal from sensor 30 whilescanner 100 is in the second power-saving mode.

A mode switching process for switching among the above-described modesis described with reference to FIG. 8. The mode switching process may beperformed by power supply control device 53 when power source device 51is connected to the main electricity grid or the battery and power issupplied to power supply control device 53 from power source device 51.

As the mode switching process starts, first, power supply control device53 may operate in the ready mode in an initial state (step S101). It maybe expected that scanner 100 will probably be used immediately afterscanner 100 is up. Therefore, the mode may preferably be the ready modeimmediately after scanner 100 is up.

After step S101, power supply control device 53 may start the timer tomeasure time (step S102). The time being measured by the timer may beused for a mode switching determination. The measured time of the timermay be reset to an initial value when document reading is started. Thetimer may stop measuring time during document reading, and the timer mayrestart measuring time when the document reading is completed. Themeasured time of the timer may be reset to the initial value whencontrol device 10 detects a user operation through operating panel 40 orreceipt of a signal from the external device.

Then, power supply control device 53 may determine whether communicationis available between scanner 100 and an external device (step S151). Theexternal device may be the USB memory connectable to scanner 100 via USBinterface 15 or the PC connectable to scanner 100 via network interface16.

When communication is available between scanner 100 and an externaldevice (step S151: YES), power supply control device 53 may specify atime period T1 (for example, 15 minutes) as the threshold time periodfor shifting to the power saving mode (step S152). When communication isnot available between scanner 100 and an external device (step S151:NO), power supply control device 53 may specify a time period T2 (forexample, 3 minutes) as the threshold time period to further reduce thepower consumption in scanner 100 (step S153). Time period T2 may beshorter than time period T1. After step S152 or step S153, the routinemay move to step S103.

Then, power supply control device 53 may determine whether document feedtray 91 has been changed from the used position to the unused position(step S103). Power supply control device 53 may determine the positionof document feed tray 91 based on the output signal sent from sensor 30.In step S103, when sensor 30 detects the position change of documentfeed tray 91 from the used position to the unused position, power supplycontrol device 53 may make a positive determination (step S103: YES).From then on, power supply control device 53 may not make the positivedetermination in step S103 until sensor 30 detects again the positionchange of document feed tray 91 from the used position to the unusedposition.

When document feed tray 91 has been changed from the used position tothe unused position (step S103: YES), power supply control device 53 maydetermine whether the elapsed time measured by the timer has exceededthe threshold time period (step S104). When the elapsed time measured bythe timer has exceeded the threshold time period (step S104: YES), powersupply control device 53 may perform a second power-saving modeexecuting process by shifting to the second power-saving mode (stepS105).

FIG. 9 depicts details of the second power-saving mode executing processin step S105. In the second power-saving mode executing process, first,power supply control device 53 may change the mode to the secondpower-saving mode (step S181). In step S181, power supply control device53 may output the signal for supplying or not supplying power to eachpower source system with respect to switch circuit 52 to control switchcircuit 52 for changing the power-supply mode. This may be realized bythe switching of the power supply condition by switching switch circuit52 between supplying and not supplying power to each power source systemin the second power-saving mode. That is, when document feed tray 91 islocated in the unused position, the user may not be allowed to operateoperating panel 40 or to set one or more documents 9 on document feedtray 91. Therefore, it may be conceivable that the user may not intendto use scanner 100. Thus, power supply control device 53 may change themode to the second power-saving mode for more effectively reducing thepower consumption in scanner 100.

Then, power supply control device 53 may determine whether document feedtray 91 has been changed from the unused position to the used positionbased on the output signal from sensor 30 (step S182). While documentfeed tray 91 is located in the unused position (step S182: NO), theroutine may wait until document feed tray 91 is changed from the unusedposition to the used position.

When document feed tray 91 has been changed to the used position (stepS182: YES), power supply control device 53 may change the mode to theready mode (step S183). In step S183, power supply control device 53 mayoutput the signal for supplying or not supplying power to each powersource system with respect to switch circuit 52 to control switchcircuit 52 for changing the power-supply mode. This may be realized bythe switching of the power supply condition by switch circuit 52 betweensupplying and not supplying power to each power source system in theready mode, because it may be conceivable that the user will use scanner100. Then, power supply control device 53 may reset the measured time ofthe timer to the initial value and restart the timer to measure time(step S184). After step S184, power supply control device 53 may exitthe second power-saving mode executing process.

Back to the mode switching process of FIG. 8, after performing thesecond power-saving mode executing process in step S105, the routine maymove to step S151.

When the elapsed time measured by the timer has not exceeded thethreshold time period (step S104: NO), power supply control device 53may determine whether scanner 100 is currently performing documentreading (step S131). The measured time of the timer may be reset whendocument reading is started and the timer may stop measuring time duringdocument reading. Therefore, the elapsed time measured by the timer doesnot exceed the threshold time period when scanner 100 is currentlyperforming document reading. Thus, the case where the elapsed timemeasured by the timer has not exceeded the threshold time period mayinclude a case where scanner 100 is currently performing documentreading and a case where the elapsed time has not exceeded the thresholdtime period since the document reading was completed.

When scanner 100 is currently performing document reading (step S131:YES), power supply control device 53 may cancel the reading of one ormore documents following the current target document after a time periodduring which the current target document is read is over (step S132).That is, when scanner 100 stops the current document reading in themiddle of reading the current target document, scanner 100 may notobtain completely-read image data. Even when scanner 100 restarts thereading of the current target document, the quality of an image may bedegraded due to variations in the reading speed. Accordingly, scanner100 may continue the reading of the document being currently read tocomplete the reading of the current target document. However, scanner100 may not perform reading of any documents following the currenttarget document because a problem may arise during the conveyance of thefollowing documents. After the completion of step S132, the currentdocument reading is completed. Therefore, power supply control device 53may restart the timer, which has stopped, to measure time. After stepS132 or when scanner 100 is not currently performing the documentreading (step S131: NO), the routine may move to step S151.

Back to step S103, when document feed tray 91 has not been changed fromthe used position to the unused position (step S103: NO), power supplycontrol device 53 may determine whether document feed tray 91 has beenchanged from the unused position to the used position (step S111). Instep S111, when sensor 30 detects the position change of document feedtray 91 from the unused position to the used position, power supplycontrol device 53 may make a positive determination (step S111: YES).From then on, power supply control device 53 may not make the positivedetermination until sensor 30 detects the position change of documentfeed tray 91 from the unused position to the used position.

When document feed tray 91 has been changed from the unused position tothe used position (step S111: YES), power supply control device 53 maychange to the ready mode (step S112). In step S112, power supply controldevice 53 may output the signal for supplying or not supplying power toeach power source system with respect to switch circuit 52 to controlswitch circuit 52 for changing the power-supply mode. This may berealized by switching the power supply condition by switch circuit 52between supplying and not supplying power to each power source system inthe ready mode. That is, power supply control device 53 may controlswitch circuit 52 to supply power to each unit or each component ofscanner 100 and thus scanner 100 may be allowed to perform documentreading. When scanner 100 is in the ready mode at the time of theposition change of document feed tray 91 from the unused position to theused position, power supply control device 53 may not need to performstep S112. After step S112, power supply control device 53 may reset themeasured time of the timer to the initial value and restart the timer tomeasure time (step S113). After step S113, the routine may move to stepS151.

When document feed tray 91 has not been changed from the unused positionto the used position (step S111: NO), power supply control device 53 mayperform a power saving mode switching process for determining whether anautomatic mode change to the first or second power-saving mode isperformed (step S121).

FIG. 10 depicts details of the power saving mode switching process instep S121. In the power saving mode switching process, first, powersupply control device 53 may determine whether the elapsed time measuredby the timer has exceeded the threshold time period (step S201). Whenthe elapsed time measured by the timer has exceeded the threshold timeperiod (step S201: YES), power supply control device 53 may determinewhether document feed tray 91 is located in the used position (stepS202).

When document feed tray 91 is located in the used position (step S202:YES), power supply control device 53 may change the mode to the firstpower-saving mode (step S203). In step S203, power supply control device53 may output the signal for supplying or not supplying power to eachpower source system with respect to switch circuit 52 to control switchcircuit 52 for changing the power-supply mode. This may be realized byswitching the power supply condition by switch circuit 52 betweensupplying and not supplying power to each power source system in thefirst power-saving mode. In the first power-saving mode, power supplycontrol system 50 may control switch circuit 52 to stop supplying powerto image reading unit 20 while continuing to supply power to operatingpanel 40, the external interface, and control device 10 that may controloperating panel 40 and the external interface. Therefore, in the firstpower-saving mode, scanner 100 may be allowed to receive an inputthrough operating panel 40 or an input from the external device. Whenscanner 100 has already been in the first power-saving mode at the timeof step S203, power supply control device 53 may not need to performstep S203.

When document feed tray 91 is located in the unused position (step S202:NO), power supply control device 53 may perform the second power-savingmode executing process (step S221). In the second power-saving mode,power supply control system 50 may control switch circuit 52 to stopsupplying power to image reading unit 20, the external interface, andcontrol device 10 that may control operating panel 40 and the externalinterface. Therefore, in the second power-saving mode, scanner 100 maynot be allowed to receive an input from the external device. Theprocessing of step S221 may be the same as the processing of step S105.After completing step S221, power supply control device 53 may exit thepower saving mode switching process.

After step S203 or when the elapsed time measured by the timer has notexceeded the threshold time period (step S201: NO), power supply controldevice 53 may determine whether scanner 100 has received a useroperation (step S204). The user operation to scanner 100 may be, forexample, an input operation on operating panel 40, an issue of ascanning instruction from the PC, or an access to data from the PC. Whenscanner 100 has not received a user operation (step S204: NO), powersupply control device 53 may exit the power saving mode switchingprocess.

When scanner 100 has received a user operation (step S204: YES), powersupply control device 53 may change the mode to the ready mode (stepS205). In step S205, power supply control device 53 may output thesignal for supplying or not supplying power to each power source systemwith respect to switch circuit 52 to control switch circuit 52 forchanging the power-supply mode. This may be realized by the switching ofthe power supply condition by switch circuit 52 between supplying andnot supplying power to each power source system in the ready mode forperforming processing corresponding to the user operation. That is,power supply control system 50 may control switch circuit 52 to supplypower to each unit or each component of scanner 100 and this scanner 100may be allowed to perform document reading. When scanner 100 has alreadybeen in the ready mode at the time of step S205, power supply controldevice 53 may not need to perform step S205. After step S205, powersupply control device 53 may reset the measured time of the timer to theinitial value and restart the timer to measure time (step S206). Afterstep S206, power supply control device 53 may exit the power saving modeswitching process.

Back to the mode switching process of FIG. 8, after performing the powersaving mode switching process of step S121, the routine may move to stepS151.

As described above, in scanner 100 according to the illustrativeembodiment, while scanner 100 does not perform reading of a document 9,the user convenience may be ensured by the mode change to the powersaving mode (in particular, the second power-saving mode in thisillustrative embodiment) performed in accordance with the positionchange of document feed tray 91 from the used position to the unusedposition document 9. When document feed tray 91 is changed from the usedposition to the unused position during document reading, the mode maynot be changed to the first power-saving mode or the second power-savingmode while at least reading of the current target document is performed.By doing so, the currently-performed reading may be completed and thusthe degradation in the image quality may be reduced. Accordingly,scanner 100 according to the illustrative embodiment may achieveimage-reading quality and the user convenience.

While various aspects of the disclosure has been described in detailwith reference to the specific illustrative embodiments thereof, itwould be apparent to those skilled in the art that various changes,arrangements and modifications may be applied therein without departingfrom the spirit and scope of the invention. For example, theimage-reading device may not be limited to the scanner but may beapplied to any devices having a reading function, for example,multifunction peripheral devices or facsimile machines.

In the above-described illustrative embodiment, the mode may be changedto the first or second power-saving mode on condition that document feedtray 91 is located in the used position or in the unused position,respectively. The condition may not be limited to the specificillustrative embodiment. In other illustrative embodiments, for example,the mode may be changed to the first or second power-saving mode oncondition that document discharge tray 92 is located in the usedposition or in the unused position, respectively. That is, in theabove-described illustrative embodiment, the power supply may becontrolled in accordance with the position (the used position or theunused position) of document feed tray 91. Nevertheless, in otherillustrative embodiments, for example, the power supply may becontrolled in accordance with the position (the user position or theunused position) of document discharge tray 92.

In the above-described illustrative embodiment, there may be threemodes, for example, the ready mode, the first power-saving mode, and thesecond power-saving mode. Nevertheless, in other illustrativeembodiments, for example, the mode may be changed between two modes, forexample, the ready mode and the second power-saving mode (or the firstpower-saving mode). There may be other modes (for example, a thirdpower-saving mode in which power supply control system 50 may controlswitch circuit 52 to stop supplying power to the external interfacewhile continuing the power supply to control device 10 for a duration ofthe mode shifting from the first power-saving mode to the secondpower-saving mode).

In the above-described illustrative embodiment, power source device 51may supply power to operating panel 40 at all times. Nevertheless, inother illustrative embodiments, for example, power supply control system50 may control switch circuit 52 to stop supplying power to operatingpanel 40 in the second power-saving mode.

In the above-described illustrative embodiment, when document feed tray91 is located in the unused position (step S103: YES), power supplycontrol device 53 may change the mode to the second power-saving modeafter the elapsed time measured by the timer exceeds the threshold timeperiod (step S104: YES). However, it may be unnecessary to wait at alltimes until the elapsed time measured by the timer exceeds the thresholdtime period. In other illustrative embodiments, for example, powersupply control device 53 may change the mode to the second power-savingmode immediately after document feed tray 91 is changed from the usedposition to the unused position (or immediately after document readingis completed when scanner 100 is performing the document reading). Theimmediate mode change to the second power-saving mode after the positionchange of document feed tray 91 from the used position to the unusedposition may achieve further power savings.

In the above-described illustrative embodiment, power supply controldevice 53 may change the threshold time period based on whethercommunication is available between scanner 100 and an external device.Nevertheless, in other illustrative embodiments, for example, thethreshold time period may not change.

In the above-described illustrative embodiment, when document feed tray91 is changed from the used position to the unused position, scanner 100may continue the reading of the document being read. Nevertheless, inother illustrative embodiments, for example, scanner 100 may beconfigured to perform reading of all of the following documents placedon document feed tray 91 when document feed tray 91 is changed to theunused position. However, the following documents may be damaged becauseit may be difficult to convey the documents from document feed tray 91that may be located in the unused position. Accordingly, it may bepreferable to complete the reading of the current target document onlyand not to perform reading of the following documents.

In the above-described illustrative embodiment, the threshold timeperiod for shifting to the first power-saving mode and the thresholdtime period for shifting to the second power-saving mode may be commonlyused. Nevertheless, in other illustrative embodiments, for example,these threshold time periods may be individually specified. In thiscase, for example, the threshold time periods may be individuallyspecified based on whether communication is available between scanner100 and an external device.

In the above-described illustrative embodiment, when scanner 100 is inthe first power-saving mode, power supply control device 53 may controlswitch circuit 52 to stop supplying power to image reading unit 20 toreduce the power consumption in scanner 100. Nevertheless, in otherillustrative embodiments, for example, power supply control device 53may decrease the power supplied to image reading unit 20 to reduce thepower consumption in scanner 100, instead of stopping the power supply.In the above-described illustrative embodiment, when scanner 100 is inthe second power-saving mode, power supply control device 53 may controlswitch circuit 52 to stop supplying power to control device 10 and theexternal interface in addition to image reading unit 20. Similarly,power supply control device 53 may decrease the power supplied to atleast one of image reading unit 20, control device 10, and the externalinterface to reduce the power consumption in scanner 100.

While the disclosure has included various example structures andillustrative embodiments, it will be understood by those skilled in theart that other variations and modifications of the structures andembodiments described above may be made without departing from the scopeof the disclosure. Other structures and embodiments will be apparent tothose skilled in the art from a consideration of the specification orpractice of the embodiments disclosed herein. It is intended that thespecification and the described examples are illustrative.

What is claimed is:
 1. An image-reading apparatus, comprising: a housing; a roller configured to convey a document along a conveying path; a contact image sensor configured to read the conveyed document; a document tray connected to the housing pivotally between a first position and a second position; a sensor configured to output a signal identifying a position of the document tray; a power supply device electrically connected to the contact image sensor, the power supply device being configured to supply power to the contact image sensor; and a controller configured to: control the power supply device to maintain the supply of power to the contact image sensor when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position and the contact image sensor is reading and the roller is conveying; and control the power supply device to reduce the power supplied to the contact image sensor when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position after last performing document reading.
 2. The image-reading apparatus according to claim 1, wherein the reducing the power supplied to the contact image sensor comprises reducing the power supplied to the contact image sensor when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position and when, since last performing document reading, a predetermined time period has elapsed.
 3. The image-reading apparatus according to claim 1, wherein the controller is further configured to control the power supply device to: reduce the power supplied to the contact image sensor when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position and the contact image sensor is not reading and the roller is not conveying.
 4. The image-reading apparatus according to claim 1, wherein the reducing the power supplied to the contact image sensor comprises stopping the supply of power to the contact image sensor.
 5. The image-reading apparatus according to claim 2, wherein the controller is further configured to: reset a timer when the position of the document tray, identified by the signal from the sensor, has changed from the second position to the first position and the predetermined time period has not elapsed.
 6. The image-reading apparatus according to claim 5, wherein, the controller is further configured to control the power supply device to: reduce the power supplied to the contact image sensor when the predetermined time period has elapsed since the timer was reset.
 7. The image-reading apparatus according to claim 1 further comprises: an external interface configured to communicate with an external device, wherein the controller is further configured to: allow communication with the external device to continue via the external interface when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position and the contact image sensor is reading and the roller is conveying; and cause communication with the external device to be discontinued via the external interface when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position and after last performing document reading.
 8. The image-reading apparatus according to claim 1 further comprises: an operating panel provided on the housing, wherein the power supply device is electrically connected to the operating panel and is configured to supply power to the operating panel, and wherein the controller is further configured to control the power supply device to: continue supplying the power to the operating panel when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position and when the contact image sensor is performing reading and the roller is conveying; and reduce the power supplied to the operating panel when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position after last performing document reading.
 9. An image-reading apparatus, comprising: a housing; a roller configured to convey a document along a conveying path; a contact image sensor configured to read the conveyed document; a document tray connected to the housing pivotally between a first position and a second position; a sensor configured to output a signal identifying a position of the document holding portion; an external interface configured to communicate with an external device; and a controller configured to: allow communication with the external device via the external interface to continue when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position and the contact image sensor is reading the document and the roller is conveying the document; and cause communication with the external device via the external interface to be discontinued when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position after last performing document reading.
 10. The image-reading apparatus according to claim 9, wherein the allowing the communication to continue comprises causing the communication with the external device via the external interface to continue when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position and since last performing document reading, a predetermined time period has elapsed.
 11. The image-reading apparatus according to claim 9, wherein the controller is further configured to: cause communication with the external device via the external interface to be discontinued when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position and when the contact image sensor is not reading and the roller is not conveying.
 12. The image-reading apparatus according to claim 9, wherein the causing communication with the external device via the external interface to be discontinued comprises stopping the supply of power to the external interface.
 13. The image-reading apparatus according to claim 10, wherein the controller is further configured to: reset a timer when the position of the document tray has changed from the second position to the first position and the predetermined time period has not elapsed.
 14. The image-reading apparatus according to claim 13, wherein, the controller is further configured to: cause communication with the external device via the external interface to be discontinued when the predetermined time period has elapsed since the timer was reset.
 15. An image-reading apparatus, comprising: a housing; a roller configured to convey a document along a conveying path; a contact image sensor configured to read the conveyed document; a document tray connected to the housing pivotally between a first position and a second position; a sensor configured to output a signal identifying a position of the document tray; an operating panel provided on the housing; a power supply device electrically connected to the contact image sensor, sensor, and the operating panel, the power supply device being configured to supply power to the contact image sensor, the sensor, and the operating panel; and a controller configured to control the power supply device to set a power-supply mode of the image-reading apparatus, the power-supply mode includes a first mode and a second mode, the first mode includes supplying the power to both the contact image sensor and the operating panel, and the second mode includes reducing the power supplied to at least one of the contact image sensor and the operating panel relative to the power supplied in the first mode, wherein the controller is configured to: set the power-supply mode to the first mode when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position and when the contact image sensor is reading and the roller is conveying; and set the power-supply mode to the second mode when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position after last performing document reading.
 16. The image-reading apparatus according to claim 15, wherein the setting the power-supply mode to the second mode comprises setting the power-supply mode to the second mode when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position and when, since last performing document reading, a predetermined time period has elapsed.
 17. The image-reading apparatus according to claim 15, wherein the controller is further configured to control the power supply device to: set the power-supply mode to the second mode when the position of the document tray, identified by the signal from the sensor, has changed from the first position to the second position and when the contact image sensor is not reading and the roller is not conveying.
 18. The image-reading apparatus according to claim 15, wherein the second mode includes stopping the supply of power to the at least one of the contact image sensor and the operating panel to reduce the power supplied.
 19. The image-reading apparatus according to claim 16, wherein the controller is further configured to: reset a timer when the position of the document tray, identified by the signal from the sensor, has changed from the second position to the first position and the predetermined time period has not elapsed.
 20. The image-reading apparatus according to claim 19, wherein, the controller is further configured to control the power supply device to: set the power-supply mode to the second mode when the predetermined time has elapsed since the timer was reset.
 21. The image-reading apparatus according to claim 15 wherein the controller is further configured to control the power supply device to supply the power to the sensor both in the first mode and the second mode. 